Role of dopamine D3 receptors in the addictive properties of ethanol.

After the cloning of the dopamine D(1) and D(2) receptors (1-3), several additional dopamine receptors were identified. These new subtypes included the D(3) and D(4) receptors, which are similar to D(2), and the D(5) receptor, which is similar to D(1) (4-6). Although most studies have focused on the role of dopamine D(1) and D(2) receptors in mediating the addictive liability of drugs, the lack of selective pharmacological tools has significantly hampered this particular field of research. In contrast, recent studies using selective competitive antagonists have shown that the dopamine D(3) receptor is involved in drug-seeking behavior. The present review is intended to highlight a new, promising area in alcohol research that focuses on the role of the dopamine D(3) receptor in the addictive properties of ethanol.